Method and apparatus for producing an oxide-free hot-formed product



J1EE}? 38, 19%? D. B. CQFER BfiEfiJZffi METHOD AND APPARATUS FOR PRODUCING AN OXIDE-FREE HOT-FORMED PRODUCT Filed April 5, 1966 IP16. 3 j

zz vvzNroj? Daniel B C01??? United States Patent 3,331,123 METHUD AND APPARATUS FOR PRQDUCING AN OXiDlE-FREE HGT-FORMED PRODUCT Daniel B. Cofer, Carrollton, Ga, assignor to Southwire Company, Carroiiton, Ga., incorporation of Georgia Filed Apr. 5, 1966, Ser. No. 540,373 8 Claims. (Cl. 29528) ABSTRACT OF THE DISCLOSURE What is disclosed herein is a method of and apparatus for producing a substantially oxide-free hot-formed product. The method and apparatus are disclosed in terms of a casting means and a hot-forming means positioned for a cast metal to pass directly from the casting means to the hot-forming means through a cleaning means for removing surface oxides from the cast metal with rotating brushes or a plurality of scrapers.

This invention relates to the hot-forming of metal and, more particularly to a method of and apparatus for producing a substantially oxide-free hot-formed product directly from molten metal.

The production of hot-formed products directly from molten metal as an integrated process involving the casting of molten metal to obtain cast metal and the subsequent hot-forming of the cast metal without significant intervening cooling of the cast metal is well known in the art and is well suited to providing a substantially oxidefree hot-formed product. This is because the conveying of cast-metal substantially directly from a casting means to a hot-forming means provides less opportunity for an oxide coating to form on the cast metal than is provided by other prior art processes involving the cooling, sometimes storing, and reheating of cast metal between the casting means and the hot-forming means. However, even in a process of producing a hot-formed product directly from molten metal, some undesirable oxide coating is formed on the cast metal between the casting means and the hot-forming means.

This oxide coating is undesirable because it tends to become imbedded in the metal during hot-forming so as to reduce the strength, ductility and conductivity of the resulting hot-formed product. Moreover, this oxide coating produces a drab, unsightly surface on the resulting hot-formed product which often interferes with subsequent working, such as by wire drawing, of the hot-formed product.

Thus, even a process for producing a hot-formed product directly from molten metal must provide for removing or preventing the formation of an oxide coating on the cast metal between the casting means and the hot-forming means if a substantially oxide-free hot-formed product is to be produced. The invention disclosed herein produces a substantially oxide-free hot-formed product directly from molten metal by providing for the removal of an oxide coating from the cast metal in a manner not obtainable in the prior art without the use of relatively expensive and dilficult to use and maintain cleaning or reducing devices.

Specifically, the invention disclosed herein is embodied in apparatus comprising a casting means of conventional type, a hot-forming means of conventional type, and a relatively inexpensive cleaning means for mechanically removing an oxide coating from the cast metal as the cast metal passes between the casting means and the hot-forming means. The cleaning means effectively removes any oxide coating on the cast metal prior to hot-forming and since the removal of the oxide coating is mechanically accomplished, the invention avoids the relatively expensive and difficult to use and maintain prior art cleaning or reducing devices which have been used to provide an environment between the casting means and the hot-forming means for removing or preventing the formation of an oxide coating.

These and other features and advantages of the inven tion will be more clearly understood from the following detailed description and the accompanying drawings in which like characters of reference designate corresponding parts throughout and in which:

FIG. 1 is a schematic presentation of the invention showing the elements thereof and their relationship to each other;

FIG. 2 is a sectional view of one embodiment of the cleaning means of the invention taken substantially along line 22 in FIG. 1;

FIG. 3 is a sectional view of a second embodiment of the cleaning means of the invention taken along the same line in FIG. 1 as FIG. 2.

These figures and the following detailed description disclose a specific embodiment of the invention but the invention is not limited to the details disclosed herein since it may be embodied in other equivalent forms.

The invention disclosed herein is best understood as comprising a casting means C, a hot-forming means H, and a cleaning or oxide removal means L. The casting means C is of conventional design comprising a casting wheel 10, an idler wheel 11 and band 12 enclosing the casting wheel 10 and the idler wheel 11. The casting means C is shown only schematically because it will be understood that the band 12 serves to define a mold (not shown) with an annular groove (not shown) in the casting wheel 10 into which molten metal is poured and from which a cast bar 13 is ejected as shown in FIG. 1.

The casting means C and the hot-forming means H are positioned relative to each other so that the cast bar 13 passes directly from the casting means C to the hot-forming means H without substantial cooling thereof as is conventional in the production of a hot-formed product directly from molten metal. Like the casting means C, the hotforming means H is of conventional type in that it includes a plurality of roll stands 14 positioned to receive and hotform the cast bar 13 in sequence.

In the invention, the casting means C and the hotforming means H are combined with the cleaning means L positioned between the casting machine C and the hotforming means H. The cleaning means L may be any device which will engage the cast bar 13 as it passes between the casting means C and the hot-forming means H and mechanically remove any oxide coating on the cast bar 13 subsequent to the cast bar 13 :being ejected from the casting means C and prior to the cast bar 13 being received in the hot-forming means H. Two embodiments of the cleaning means L are disclosed herein.

In FIG. 2 is shown an embodiment of the cleaning means L comprising a plurality of cylindrical wire brushes 16 positioned within the frame 15 of the cleaning means L. Each wire brush 16 includes a shaft 17 having its ends journalled in conventional manner in an inner wall -18 formed within the frame 15 of the cleaning means L. A plurality of rigid wire bristles 19 extend from each of the shafts 17 of the wire brushes 16 and the wire brushes 16 are positioned within the frame 15 of the cleaning means L so that the bristles 19 of the wire brushes 16 enclose the cast bar 13 as it passes through the cleaning means L.

In that embodiment of the cleaning means L shown in FIG. 2 the enclosing of the cast bar 13 by the bristles 19 of the wire brushes 16 is accomplished by positioning three wire brushes 16 to form a triangular opening conforming to the triangular cross section of the cast bar '13 and through which the cast bar 13 passes. However, it will be understood that the positioning of the wire brushes 16 is varied if the cast bar 13 has a circular, square, or other cross section which is not triangular.

Moreover, it will be understood that the wire brushes 16 are disposed relative to each other along the length of the cast bar 13 so that the Wire brushes 16 do not interfere with each other. More importantly, it will be understood that when the wire brushes 16 are rotated at a proper rotational speed by any convenient driving mechanism such as motors positioned on the frame 15 to drive one end of each shaft 17, the bristles 19 of the wire brushes 16 engaging the cast bar 13 move relative to the surface of the cast bar 13 and serve to remove from the surface of the cast bar 13 any oxide coating thereon.

In that embodiment of the cleaning means L shown in FIG. 3, a plurality of scrapers 22 formed of tool steel or the like are positioned within the frame 15 of the cleaning means L so that together they form a triangular opening 23 conforming to the cross sectional shape of the cast bar 13. Each scraper 22 is fixedly positioned within the frame 15 of the cleaning means L by extending a pin 26 from the scraper 22 to an inner wall 18 within the frame 15. Although the three scrapers 22 in that embodiment of the cleaning means L shown in FIG. 3 are arranged to provide the triangular opening 23 required to conform to the triangular cross section of the cast bar 13, it will be understood that a plurality of scrapers 22 may be arranged to completely surround the cast bar 13 as it passes through the cleaning means L regardless of the cross sectional shape of the cast bar 13.

It will also be understood that the opening 23 provided by the scrapers 22 is slightly smaller than the cross section of the cast bar 13 and that the passing of the cast bar 13 through the opening 23 results in a layer of metal being scraped from the cast bar 13 which contains any oxide coating which has been formed on the cast 13. To more efficiently accomplish this, each scraper 22 has those edges 24 defining its innermost surface 25 sharpened in conventional manner. From the foregoing, it will now be understood that the invention disclosed herein provides an oxide-free hotformed product by minimizing the formation of an oxide coating on the cast bar .13 through the positioning of the hot-forming means H relative to the casting means C and by providing a cleaning means L between the hot-forming means H and the casting means C which mechanically removes any oxide coating on the cast bar 13 as the cast bar 13 passes between the casting means C and the hotforming means H. Moreover, it will be obvious from the two embodiments of the cleaning means L disclosed herein that brushes 16, scrapers 22, or a variety of other devices may be used to accomplish the mechanical removal of an oxide coating from the cast "bar 13 as it passes between the casting means C and the hot-forming means H.

It will also be obvious to those skilled in the art that many variations may be made in the embodiments chosen for the purpose of illustrating the present invention without departing from the scope thereof as defined by the appended claims.

What is claimed as invention is:

1. In an apparatus for producing a hot-formed product directly from molten metal; casting means for casting molten metal to obtain cast metal; hot-forming means for hot-forming said cast metal into a hot-formed product, said hot-forming means being positioned to receive said cast metal directly from said casting means without substantial cooling of said cast metal occurring between said casting means and said hot-forming means; and cleaning means positioned between said casting means and said hot-forming means for mechanically removing 0X- ides from said cast metal as said cast metal passes between said casting means and said hot-forming means, said cleaning means consisting of rotating wire brushes in a configuration which conforms to the periphery of said cast metal.

2. In an apparatus for producing a hot-formed prodnot directly from molten metal; casting means for easting moltenv metal to obtain cast metal; hot-forming means for hot-forming said cast metal into a hot-formed product, said hot-forming means being positioned to receive said cast metal directly from said casting means without substantial cooling of said cast metal occurring between said casting means and said hot-forming means; and

cleaning means positioned between said casting means and said hot-forming means for mechanically removing oxides from said cast metal as said cast metal passes between said casting means and said hot-forming means, said cleaning means consisting of a plurality of scrapers in a configuration which conforms to the periphery of said cast metal.

3. The apparatus of claim 1 in which said hot-forming means includes a plurality of roll stands positioned to receive and hot-form said cast metal in sequence.

4. The apparatus of claim 2 in which said hot-forming means includes a plurality of roll stands positioned to receive and hot-form said cast metal in sequence.

5. The apparatus of claim 3 in which said casting means includes a casting wheel.

6. The apparatus of claim 4 in which said casting means includes a casting wheel.

7. In a method of producing a hot-formed product directly from molten metal, the steps of casting molten metal in a casting means to obtain cast metal, passing said cast metal to a hot-forming means without substantial cooling of said cast metal between said casting means and said hot-forming means, mechanically removing oxides from said cast metal between said casting means and said hot-forming means by passing said cast metal through rotating wire brushes in a configuration which conforms to the periphery of said cast metal, and hot-forming said cast metal into a hotformed product in said hot-forming means.

8. In a method of producing a hot-formed product directly from molten metal, the steps of casting molten metal in a casting means to obtain cast metal, passing said cast metal to a hot-forming means without substantial cooling of said cast metal between said casting means 1 and said hot-forming means, mechanically removing oxides from said cast metal between said casting means and said hot-forming means by passing said cast metal through a plurality of scrapers in a configuration which conforms to the periphery of said cast metal, and hot-forming said cast metal into a hot-formed product in said hot-forming means.

References Cited UNITED STATES PATENTS 1,386,107 8/1921 Hamilton 2257.3 X 2,019,496 11/1935 Kohlhaas.

2,709,842 6/1955 Findlay 29-333 X 2,710,433 6/1955 Properzi 22-200.l X

JOHN F. CAMPBELL, Primary Examiner.

R. F. DROPKIN, Assistant Examiner. 

1. IN AN APPARATUS FOR PRODUCING A HOT-FORMED PRODUCT DIRECTLY FROM MOLTEN METAL; CASTING MEANS FOR CASTING MOLTEN METAL TO OBTAIN CAST METAL; HOT-FORMING MEANS FOR HOT-FORMING SAID CAST METAL INTO A HOT-FORMED PRODUCT, SAID HOT-FORMED MEANS BEING POSITIONED TO RECEIVE SAID CAST METAL DIRECTLY FROM SAID CASTINGS MEANS WITHOUT SUBSTANTIAL COOLING OF SAID CAST METAL OCCURRING BETWEEN SAID CASTING MEANS AND SAID HOT-FORMING MEANS; AND CLEANING MEANS POSITIONED BETWEEN SAID CASTING MEANS AND SAID HOT-FORMING MEANS FOR MECHANICALLY REMOVING OXIDES FROM SAID CAST METAL AS SAID CAST METAL PASSES BETWEEN SAID CASTING MEANS AND SAID HOT-FORMING MEANS, SAID CLEANING MEANS CONSISTING OF ROTATING WIRE BRUSHES IN A CONFIGURATION WHICH CONFORMS TO THE PERIPHERY OF SAID CAST METAL.
 8. IN A METHOD OF PRODUCING A HOT-FORMED PRODUCT DIRECTLY FROM MOLTEN METAL, THE STEPS OF CASTING MOLTEN METAL IN A CASTING MEANS TO OBTAIN CAST METAL, PASSING SAID CAST METAL TO A HOT-FORMING MEANS WITHOUT SUBSTANTIAL COOLING OF SAID CAST METAL BETWEEN SAID CASTING MEANS AND SAID HOT-FORMING MEANS, MECHANICALLY REMOVING OXIDES FROM SAID CAST METAL BETWEEN SAID CASTING MEANS AND SAID HOT-FORMING MEANS BY PASSING SAID CAST METAL THROUGH A PLURALITY OF SCRAPERS IN A CONFIGERATION WHICH CONFORMS TO THE PERIPHERY OF SAID CAST METAL, AND HOT-FORMING SAID CAST METAL INTO A HOT-FORMED PRODUCT INSAID HOT-FORMING MEANS. 